Produção da mamoneira submetida a combinações com fontes de fósforo e calagem

Abstract

R E S U M OA mamoneira é considerada cultura exigente em fósforo haja vista que a nutrição fosfatada adequada com a utilização de fontes solúveis em conjunto com fontes naturais, pode aumentar a eficiência de absorção do fósforo e a produtividade de mamona. Objetivou-se avaliar os componentes de produção da mamoneira após a combinação de adubações com fosfato solúvel e natural, na ausência e na presença de calagem. O estudo foi conduzido em esquema fatorial 2 x 5 envolvendo duas doses de calcário (com e sem calcário) e cinco combinações de adubação fosfatada: testemunha (0 kg ha -1 de P 2 O 5 ); 100% de fosfato natural (560 kg ha ) com quatro repetições em blocos ao acaso. As características avaliadas foram o comprimento dos racemos primário e secundário, o número de bagas, a massa de casca, a massa de bagas, a massa de grãos, a massa de 100 grãos e a relação entre massa de grãos/massa de bagas. A combinação de fosfato natural + MAP propiciou, na presença de calcário, maior produção de grãos de mamoneira (1.455 kg ha -1 ) e incrementou a maioria dos demais componentes de produção estudados. Production of castor bean under combination of phosphorus sources and liming A B S T R A C TCastor bean is considered a demanding crop in phosphorus and adequate phosphorus nutrition with reactive sources in conjunction with natural sources can increase the efficiency of absorption of phosphorus and castor bean productivity. This research aimed to evaluate the yield components of castor bean under combinations of fertilization with reactive and natural phosphate, in the absence and presence of lime. The study was conducted in a 2 x 5 factorial design, involving two doses of limestone (with and without lime), and five combinations of phosphorus fertilization: control (0 kg ha -1 de P 2 O 5 ), 100% of natural phosphate (560 kg ha ) and 100% MAP (188 kg ha -1 ), with four replications in a randomized block design. The length of the primary and secondary racemes, number of berries, shell weight, berry weight, grain weight, weight of 100 grains and ratio between grain and berry weight were evaluated. The combination of MAP + natural phosphate in the presence of limestone resulted in higher production of castor beans (1455 kg ha -1

Mineral fertilization with macronutrients in castor bean, lineage UFRB 222

“…In relation to the total number of fruits per plant (two racemes) (Figure 2E), the phosphate fertilization caused a quadratic effect, with maximum number of 78.90 fruits, at 581.33 kg ha -1 . Moreira et al (2012) reported average values of 27.9 fruits per raceme, in a study with the castor bean cultivar IAC Guarani as a function of phosphorus and boron, while several types of combination of fertilizations with soluble and natural phosphate had a significant effect on the number of fruits of the cultivar BRS Paraguaçu, which produced 142 fruits per plant and on average, 28.4 fruits in each raceme (Silveira et al, 2015). However, the different doses of phosphate fertilizer did not promote a significant effect on the number of fruits per plant in the cultivar Al Guarany 2002, producing 105 seeds with all treatments (Silva et al, 2013).…”

Phosphorus Doses and Sowing Times Over Agronomic Aspects of Chia

“…Phosphorus is classified as macronutrients, and without it the plant fails to develop properly. This nutrient provides a favorable environment for roots development, besides providing other nutrients in smaller proportion such as sulfur, calcium and magnesium, that according to phosphorus source used (Lima et al, 2011;Silveira et al, 2015). Their absorption is by diffusion, action in those roots find during its growth (Elz et al, 2010).…”

“…Alcantra Neto et al (2010) verified that the maintenance of soil phosphorus provides better final yield crop. This element is a component of nucleic acids and is directly related to photosynthesis and metabolic processes, as well as other benefits, such as the availability of calcium, magnesium and sulfur (Hippler et al, 2011;Silveira et al, 2015). Alcantra Neto et al (2010) note that consistent maintenance of phosphorus in the soil ensures the cultivation and significant progress in final production, as well as in helping to absorb water and other nutrients, providing resistance to cold and some diseases.…”